The invention set forth in this specification pertains to new and improved spray structures for use in watering plants. More specifically it pertains to new and improved spray structures which are adapted to be located in a fixed location and which are adapted to be used in watering only a limited area or a number of plants.
Many different types of drippers and spray structures are used and have been proposed for such use. As the irrigation field has developed many individuals have found it desirable to use spray structures which are constructed so as to each include an elongated nipple which is adapted to receive the end of a watering tube, a deflecting surface located so as to receive and deflect water from the tube passing through the nipple and a support for the nipple and deflecting surface so that the entire spray structure can be located in such a manner that the water hitting against the deflecting surface is directed toward the plant or area to be watered using the spray structure.
In the past spray structures reasonably corresponding to those described in the preceding paragraph have been formed in many different manners. An older patent relating to a spray structure having the various parts indicated in the preceding discussion is the Free U.S. Pat. No. 277,260 entitled "Grain and Fertilizer Spreading Attachment For Drills" issued in 1883. The fact that this patent is "prior art" relative to spray watering apparatus is indicated by the fact this is classified by the U.S. Patent and Trademark Office along with a variety of different although related liquid--including water-spraying devices which are adapted to be attached to ends of hoses and the like.
A comparison between the noted Free U.S. patent and the more recent Mominee U.S. Pat. No. 3,595,524 entitled "Spray Structure" issued in 1971 the more recent Roberts U.S. Pat. No. 3,638,863 entitled "Sprinkler Unit" issued in 1972 is interesting because it reveals how the field of spray structures of the type to which this invention relates has progressed or changed in the period since 1883 when the Free patent issued. Whereas the structure shown in the Free reference was apparently made of metal and was adapted to be located in an operative location by a non-illustrated structure the more recent patents noted show structures which are made of a polymer or plastic material for cost reasons and which follow the lead of a number of patents in the field so as to include a stake used to mount the disclosed structure in an intended location.
Some U.S. patents including such a stake are: the Fry U.S. Pat. No. 604,036 entitled "Hose Nozzle" issued in 1898; the Le Deit U.S. Pat. No. 2,903,190 entitled "Sprinkler Head" issued in 1959; and the Jacobs U.S. Pat. No. 3,385,525 entitled "Lawn Sprinkler" issued in 1968. It is not considered necessary to cite references to show that the use of a plastic or polymer in the Mominee and Roberts structures instead of metal is a mere substitution of materials unproductive of any unexpected results in a sprinkler structure. As a result of these considerations it is apparent that there must be functional distinctions between these latter two patents and the Free patent.
A brief inspection of the Monimee patent indicates that a distinction or difference between it and the Free patent may or can be alleged to pertain to the adjustment of the position of a distributing tube on the nipple so as to achieve a valving action controlling the flow sprayed outwardly from the device. This is easily confirmed in several ways. In the final sentence of the abstract of the Mominee patent it is indicated that: "By regulating the position of the tube upon the member with respect to the groove it is possible to control the flow of water from within the interior of the tube." The member identified in this quotation can be referred to as a nipple; the groove referenced in it is a passage for the water from the distribution tube pushed on the nipple or member. This difference is also indicated by the designation of the principle structure illustrated in the Mominee patent as ". . . a spray structure or valve 10 . . . ".
In accordance with the Mominee teachings the flow control or valving action achieved with the structures disclosed in this patent are accomplished by the adjustment of the position of the tube used relative to the end of the passage in the nipple or relative to another deflecting surface or wall located generally at the end of the such a passage. Two factors are involved with this: (1) increasing the length of confined passage between the tube and the nipple so as to increase the resistance to flow and (2) decreasing the spacing between the end of the tube and the structure so as to limit the amount of water capable of passing from the end of the tube. Of these two factors the first is considered to be relatively unimportant because of the limited amount of resistance to liquid flow normally involved in this type of device.
An understanding of the present invention does not require a detailed consideration of the issue as to whether or not a valving action as is disclosed in the Mominee patent is or is not anticipated by Free and other references. In connection with this it should, however, be noted that the Free structure is such that as the nipple element on it is screwed into a distribution tube as indicated in this patent the spacing between the end of the tube and the deflecting surface in this reference is decreased. Obviously the more this spacing is decreased the less the flow area between the deflector and the tube. This is bound to influence both the flow through the Free device and the manner in which such flow is distributed or sprayed.
The structure disclosed in the Roberts patent differs from that disclosed in the Mominee patent in that there is no valving action disclosed in connection with it. Spray devices or structures as shown in both of these prior patents do have a common feature in that in each the spray pattern achieved is dependent upon the flow through the groove or passage in the nipple and the way that this flow is deflected outwardly. Both of these references disclose deflecting surfaces which are completely transverse to or sloped with respect to the passages in the nipples employed. Water will tend to splash off of such surfaces so as to more or less oppose the flow through the passages and so as to be distributed outwardly in a somewhat irregular manner which does not produce a uniform, watering action over a comparatively large area adjacent to these devices.
It is believed that it will be apparent from this that prior structures such as are shown in the Mominee and Roberts patents are considered to be disadvantageous in that they do not provide for reasonable control of the spray pattern achieved with such structures. This is considered to be the result of the fact that such structures are of such a character that the spacing between the tubes attached to the nipples used in them and the deflecting surfaces employed in them are capable of being varied depending upon the manner in which they are used. It is also considered to be related to the fact that such prior art structures do not adequately recognize various flow considerations in the area of the deflecting surfaces used in them and, hence, do not provide a manner or mode of construction adequate to obtain a desired, relative uniform flow pattern of sprayed water adjacent to the structures shown by these references.
In no way is the preceding to be taken as indicating that spray devices as shown by the Mominee and Roberts patents are not desirable or utilitarian. They are both. Because of the manner in which they can be manufactured they can be produced in volume at a comparatively nominal cost. They can be easily used. In spite of these factors it is considered that the spray devices as shown by these references are not as desirable as they might be because of the nature of the spray pattern or patterns which can be uniformly and easily be obtained from them under "field" or similar conditions. It is also considered that these prior art devices are not as desirable as they might be because they are constructed in such a manner that a user can only use them to spray a restricted area and does not have the option of altering or changing the area sprayed with them as may be desired.